Segmentation-based parameterized motion models

A device, comprising:

• a processor, the processor configured to:
• decode, from a compressed bitstream and with respect to each reference frame of two or more reference frames available for decoding a current frame, at least two global motion models, wherein decoding a global motion model comprises decoding parameters for the global motion model, wherein the global motion models constitute multiple global motion models, and wherein each global motion model is based on a segmentation of the current frame and represents a respective underlying motion of blocks within a respective segment;
• and
• decode blocks of the current frame by configuration to:
• for each inter-predicted block of a segment, decode, from the compressed bitstream, a per block indication specific to the each inter-predicted block indicating either
• to generate a prediction block for the each inter-predicted block based on a global motion model of the multiple global motion models and associated with one of the two or more reference frames, or
• to generate the prediction block for the each inter-predicted block based on a motion vector that is different from the global motion model;
• and
• decode the each inter-predicted block based on the per block indication.

A non-transitory computer-readable medium storing instructions operable to cause one or more processors to perform operations comprising:

• decoding, from a compressed bitstream and with respect to each reference frame of two or more reference frames available for decoding a current frame, at least two global motion models, wherein decoding a global motion model comprises decoding parameters for the global motion model, wherein the global motion models constitute multiple global motion models, and wherein each global motion model is based on a segmentation of the current frame and represents a respective underlying motion of blocks within a respective segment;
• and
• decoding blocks of the current frame by:
• for each inter-predicted block of a segment, decoding, from the compressed bitstream, a per block indication specific to the each inter-predicted block indicating either
• to generate a prediction block for the each inter-predicted block based on a global motion model of the multiple global motion models and associated with the one of the two or more reference frames, or
• to generate a prediction block for the each inter-predicted block based on a motion vector that is different from the global motion model;
• and
• decoding the each inter-predicted block based on the per block indication.